Smoke eliminator and fuel



Jan. 2, 1934. w. E. FROST SMOKE ELIMINATOR AND FUEL ECONOMIZER Filed Feb. 6. 1951 INVENTOR.

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Patented Jan. 2, 1934 UNITED STATES SMOKE ELIMINATOR AND FUEL ECONOMIZER Walter E. Frost, Auburn, Maine, assignor of onehalf to Guy M. Foss and one-fourth to Harold B. Libby, both of Auburn, Maine Application February 6, 1931. Serial No. 513,967

1 Claim. (01. 110-58) One of the principal objections offered by operators of household heaters to the use of soft or bituminous coal is the impossibility, under ordinary conditions and as heaters are ,usually equipped, of procuring proper combustionof the coal gas liberated from the fuel directly after each fresh supply is added to the fire.

The escape of this gas, laden with more or less solid matter, up the chimney and over the neighl0 borhood causes a very disagreeable smoke nuisance, and to overcome or prevent this condition many devices have from time to time been devised. In some instances there has been a considerable abatement of the smoke evil by employing what are generally called smoke consumers, in others there has been but little difference in conditions arising from their use.

But it is not wholly due to the matter of uncleanliness that objection to burning soft coal in the ordinary furnace can be raised, as a very serious loss of potential heat units is suifered when unburned gas freely passes up the chimney,fuel, as it were, which if proper facilities were provided might be conserved and utilized.

Furthermore, the ordinary type of smoke eliminator is a quite expensive affair, both in material and in installation costs.

In all classes of appraratus employed for the purpose of eliminating smoke the proper application of air in connection with the consuming of the gas is of vital importance.

In the present invention, which relates to smoke eliminating and fuel economizing devices, I have ascertained by extensive experimentation that to obtain the most satisfactory results heated air should be admitted to the space through which the gas passes outwardly from the furnace, and at a point somewhere between the fire-pot and the funnel damper.

Admitted at this place the quantity of air required is much less than would be necessary if it entered the interior of the heating apparatus at any other location; and this being the case a much smaller and an extremely simplestructure accomplishes the object sought at a fraction of the cost of many of the smoke eliminators now used for the purpose under consideration.

In the specification following is found a description of my invention from which a clear understanding of its character may be obtained,

especially when taken in connection with the accompanying drawing in which a preferred embodiment thereof is illustratively disclosed.

In the drawing- Fig. 1 shows a kitchen range with my device mounted on its smoke pipe;

Figs. 2 and 3 represent slightly modified forms of the invention, in its application to a heating and power boiler, respectively;

Figs. 4 and 5 illustrate the invention in its simplest form, in end view and sectional elevation, respectively, and

Fig. 6 is a sectional elevation of the form shown in Fig. 2.

Similar reference characters are employed to identify like parts in all views of the drawing.

Referring to the drawing, 1 is a cup shaped member having a partition 2 through which are holes 3. Between the wall 1 of the cup member '70 and the partition 2 lies the chamber 4, the air in which becomes highly heated on account of the fact that the member is mounted in close proximity to the smoke pipe or funnel F, as clearly shown in the sectional view, Fig. 5.

Extending from the member 1 and passing through the wall of the funnel is a pipe 5 on the end of which is an elbow 6 from which depends the pipe 7-the last two mentioned elements being within the funnel, in the gas passageway 8 from the furnace of the range or heater.

On the lower end of the pipe '7 is a cap or nozzle 9 in which is a small orifice 10 out of which a small jet of air is delivered into the gas space in the funnel, the course of the air being through the holes 3, into the chamber 4, through the pipe 5, elbow 6 and pipe '7 and finally through the orifice 10.

In the modified form of the device shown in Figs. 2 and 6, the orifice 10 is made in the side of the pipe '7, this arrangement being preferred where two of the cups 1 are employed.

The contracted discharge opening 10 appears to have the effect of somewhat accelerating the flow of air into the gas space with a correspondingly more rapid mixing or commingling of the air and gas, and the apron or skirt 1" has been found to greatly facilitate the drafting of the air into the chamber 4 by way of the holes 3. The opening through the nozzle, or discharge end of the air-pipe, is so small that it does not serious- 1y affect or check the draft and the ingress of air is regulated by the gradual increase in temperature of the gases as the fire increases in intensitythe hotter the gases the greater the tendency to draw in the outside air.

Fig. 3 illustrates the device installed on a horizontal tubular boiler. The essential features are the same as with the device when serving as an equipment for a range or heater, except that 1119 there are two or more leader pipes 7 provided, this being for the purpose of admitting more air and distributing it at separated locations in the combustion space of the furnace.

In equipping a coal-burning furnace with my apparatus two points essential to its successful operation should be considered, one is that the air should be admitted into the gas space at a location removed from and not directly over the fuel in order that the air may act on a more condensed body or cross section of the gas than if conveyed into the more spacious combustion chamber of the fire pot: and the other is that this air should, to procure the .best. and most eiiicient results, be preheated before passing into the body of gas.

The logic of this is that heated air aids combustion, and in the present application this hot air meets the oncoming hot gases in the confined space within the smoke pipe and a rapid mixing and ignition of the combustibles takes place, the flame, once the gas is ignited feeding backward toward the fire pot and consuming the approaching smoke liberated from the coal and adding materially to the heat units utilized from the fuel.

My apparatus operates successfully, also, with hard coal or fuel oil although the advantages and beneficial results are not quite so pronounced as is the case With soft or bituminous fuel.

It is not absolutely essential that the cup member 1 be mounted-on the smoke pipe F for it might be placed on any highly heated portion of the heat generator-whether it be a range, heating boiler or power plant. It is preferred, however, to locate the device on the smoke pipe on account of the simple and less costly installing of the same; in all cases the nozzle 9 should be positioned somewhere in the gas passage between the damper D and the fire pot, the damper then being utilized to control the draft of the gas past the nozzle and permitting the air to more thoroughly mix with the gas, insuring a more complete combustion thereof.

Moreover, with an active fire the smoke pipe is usually one of the hottest portions of the heating plant.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

A device of the character described adapted to be installed on and operated in connection with heating apparatus comprising in combination with the smoke-conducting funnel, therefor, a funnel damper, a cylindrical member, having a head on one end, mounted on said funnel, a transverse partition in said member constituting one end of a chamber in said member, apertures in said partition adapted to admit air to said chamber, a cylindrical skirt extending from the peripheral wall of said member toward but spaced from said funnel, said skirt surrounding a space the air in which is adapted to be raised in temperature by radiated heat from said funnel 100 before entering said chambena pipe secured to said partition and extending through the wall of said funnel into the gas-passage-way therein, said pipe being positioned at a point located between the fire-pot for said heating apparatus and 165 the'funnel damper therefor, a second pipe disposed .in said funnel, depending from said first pipe, a cap on the lower end of said second pipe, and an aperture in said cap of less area than the inside area of said second pipe, adapted to serve 13.0 as the discharge orifice for air from said device.

'- WALTER E. FROST. 

